Temporomandibular disorders are considered a heterogeneous group of psychophysiological
disorders of the stomatognathic system (Okeson 1985, Okeson 1993) covering a broad spectrum
of muscular, skeletal or both, clinical problems (Nagamatsu-Sakaguchi, Minakuchi et al). They
are often initiated by pain, joint sounds and limited function / mandibular movement, and are
considered one of the main causal factors of non-dental orofacial pain (Rossetti et al.,
2008, Makino, Masaki et al.; Magnusson 1999). Conservative and non-invasive treatment is
considered as the one of choice at an early stage, since the symptomatology is usually
reduced through the combined use of occlusal appliences, physiotherapy and medication. (De
Leeuw, American Academy of Orofacial Pain et al., 2008) The dislocations of the articular
disc are the most common arthropathy and are characterized by several stages of clinical
dysfunction involving an abnormal interrelationship of the disc condyle complex (more often
an anterior or anteromedial disc displacement) (Isberg-Holm and Westesson 1982 ). Pain (in
acute cases), changes in mandibular movement pattern and joint noise are the most frequent
symptoms.
The causes of disc displacements are not completely established. It has been postulated that,
in most cases, the elongation or rupture of the condyle-disc ligaments allows displacement of
the disc. (Stegenga, de Bont et al., 1991) Changes in lubrication and synovial fluid quality
have also been suggested as possible etiological agents (Nitzan 2001). The presence of
osteoarthritis may also precipitate changes in the condyle-disc complex. (De Leeuw, American
Academy of Orofacial Pain et al., 2008) In addition to the intervention of the dentist with
occlusal appliance (among other resources), mandibular physiotherapy aims to reduce
musculoskeletal pain, promote muscle relaxation, reduce muscle hyperactivity, improve muscle
control and function, and maximize joint mobility . In addition to the electrotherapeutic
means there are several manual therapy techniques directed to TMJ that aim the joint
decompression, fibrosis reduction and adhesions at the level of structures such as ligaments
or joint capsule, recaptation of the articular disc or adaptation of the retrodiscal tissues.
We are talking about intraoral techniques such as condylar distraction or specific exercises
of joint mobility or muscle strengthening. (Craane, Dijkstra et al., 2012) In the specific
case of joint disc displacements, the condylar distraction technique is one of the most used
therapeutic resources. It is a technique that aims to increase the space between the
mandibular condyle and the joint fossa of the temporal, decompressing the joint and promoting
the adaptation of the articular tissues and / or the disc reuptake. It is a technique almost
exclusively performed by the physiotherapist and / or dentist, with repeated applications
over an extended period of treatment that can reach several weeks or months, difficult to
perform by the patient at home (De Leeuw, American Academy of Orofacial Pain et al, 2008).
There are currently only ambulatory mandibular exercise devices that aim to increase the
range of mandibular movement through rotation, rototranslation, and condylar translation (eg,
TheraBaccess Jaw Motion Rehab System, TheraPacer Jaw CPM ). None of these devices distracts
the joint, so in cases of acute displacement of the disc, with the presence of retrodiscal
pain, they may even be counterproductive. Thus, the development of an apparatus capable of
performing or assisting patients in the condylar distraction maneuver could prove to be a
valuable aid in the treatment of these conditions, increasing patient adherence and reducing
costs related to a long treatment time.